Bluelab Calibration fluid PH 7.01 20ml

A sealed sachet of 20 ml Bluelab pH 7.01 buffer. One calibration, fresh from the packet.

pH 7.01 sets your meter's zero point. Where the electrode should produce exactly zero millivolts. Every calibration starts here.

Why a sealed sachet sometimes beats the bottle you already own

At first glance a bottle is always better value. Yet a sachet has one property a bottle never can, and it goes to the only thing that matters about buffer solution: you know for certain the value is still right.

The whole reason you use buffer is that its pH is fixed. Once a bottle has been opened that stops being entirely true. Carbon dioxide from the air dissolves in and the value slowly shifts. Every calibration afterwards relies on a figure you can no longer check, because you have no second reference to measure your reference against.

A sealed sachet sidesteps that. It opens, gets used, and goes. There is no history for anything to have gone wrong in.

When that is worth it:

• If you calibrate rarely. A bottle used three times a year spends nine months doing nothing but ageing.
• When you distrust a reading. At that moment you do not also want to be doubting your buffer.
• When commissioning a new or freshly cleaned electrode and you want to know whether it is sound.
• On the move: a sachet weighs nothing and cannot leak or tip over.

Technical Specifications:

• Value: pH 7.01
• Volume: 20 ml, sealed sachet
• Brand: Bluelab
• Use: first calibration point (zero point) on any pH meter
• Handling: single use

Frequently asked questions

Is this the same liquid as in the bottle?
The same value, different packaging. The difference is the certainty that it is fresh.

Is one sachet enough for one calibration?
Yes. Pour it into a clean pot, calibrate, and discard the rest.

Can I keep what is left over?
Better not. Once your electrode has been in it, the liquid is no longer clean.